Prop slecetion for Marinier 40HP

[banchigu]

The boat I have has the original 1985 aluminum prop (on a 40HP Mariner) which is in good condition and not dinged up. However, I saw one on E-Bay <br /><br /> http://cgi.ebay.com/ebaymotors/ws/e...604616544&fromMakeTrack=true#ebayphotohosting <br /><br />Would it be a good idea to buy a stainless prop, if so what dia/pitch would work best for a 17 foot Bass Tracker.<br /><br />Also the trim is set on the second setting from the top to the bottom or the second to the last furthest from the boat. How do I determine this setting

 

[MercFan]

Re: Prop slecetion for Marinier 40HP

There's a nice write-up on props here at iboats<br /><br /> http://forums.iboats.com/cgi-bin/ubb/ultimatebb.cgi?ubb=get_topic;f=36;t=000030 <br /><br />And according to it, if your current diameter and pitch gives you the recommended WOT rpm, you should not change these figures.<br /><br />But basically a stainless prop is more efficient because the blades are thinner, but it's more unforgiving when you have a prop strike. Aluminiumis less efficient and more forgiving. But since your current prop is not dinged up I take it that you havn't had a prop strike, so it might be worth is going to a stainless.

 

[Moody Blue]

Re: Prop slecetion for Marinier 40HP

I just went thru changing props on my 40hp Mariner this past season. Orginal prop was 10 1/8"dia x 15" pitch on a 14 ft whaler style boat. RPM's were a little low at WOT and top speed was too fast so I changed to a 10 3/8"dia x 13" pitch and it brought the RPM's up to 5600 at WOT, right where it should be. It is also much better for pulling skiers or tubing because it has better low end torque. My top speed dropped about 5-8 MPH as well.<br /><br />On the 17ft Bass Tracker, my GUESS (and only my guess)is that the 12" pitch might be about right for the weight and size of the boat. You really should have a tach to show you actual RPM's. You won't be real fast with that combination of boat, motor and prop, maybe 25-28MPH is my guess. <br /><br />Ask the seller to confirm diameter of the prop and the number of splines on the shaft to be certain it will fit your motor. I think 11 splines is what you need but check your motor to be sure. Also, look on the existing prop for mfr and part no.